The invention relates to a gas-producing material for a gas generator, particularly for an inflatable impact cushion for protecting the passenger in a motor vehicle from injury, which consists of a combustible liquid gas mixture.
With the gas generators used at present for inflatable impact cushions (also called "airbags") a filter charge composition in tablet or disc form is used as a combustible gas-producing material. On ignition, this charge composition generates the useful gas or pressure gas for inflating the impact cushion. A disadvantage of the combustion of such solid gas-producing materials is seen in the quite high amount of slag formation during combustion, representing more than 50% of the mass of the charge composition used. Because of the slag and dust formation during combustion, expensive filter stages in the gas generator are necessary in order to hold back slag and dust particles. Otherwise, when these particles emerge, the impact cushion would be damaged and the passengers placed in danger.
As an alternative to generators containing solid materials there are generators containing compressed gases or air. In order to form a sufficient volume of gas, very high charge pressures are necessary as cooling takes place on discharge of the gases and no increase in volume can be achieved by exothermic reactions such as with solid gas-producing materials.